Wood stain



Patented May 7, 1935 Edward B. Bush,

WOOD STAIN Lemont, Ill., assignor, by m'esne assignments, to ChadeloidChemical Company, a corporation of West Virginia No Drawing.

11 Claims.

This invention relates to stains, and particuiarly stains for use onwood, to compositions usable as such and to wood articles stained withsuch compositions, together with methods of producing such articles.

The wood stains of the prior art may be looked 1 because of thegrain-raising eflect of the water certain features of disadvantage.

stain, a thin shellac coating must be applied to the stained wood inorder to stiffen the fibers in order that they may be uniformly sanded..When an open grained wood is used, it is necessary after the sandingoperation to apply a filler to the surface over which the varnish orlacquer is applied. The grain-raising effect of the water stainsseriously militates against their effectiveness. Furthermore the waterstains have indifferent penetration, the dye remaining substantially onthe top surface of the wood instead of impregnating the fibers.

The oil stains have certain features of advantage as compared with waterstains, but also They consist of a hydrocarbon solution of an anilinedye base that has been so treated, usually involving maceration or othermixing with a fatty acid such as oleic or stearic acid, as to make thedye soluble in a hydrocarbon, such as benzol, toluol or a petroleumdistillate that is so volatile as readily to evaporate when applied tothe surface to be treated, leaving the pores unimpregnated with the dye.Where such composition is applied to a wood surface having open-grain,it is customary after drying to treat the surface with a filler. Beforeapplying the usual cover coating of varnish or lacquer there must beapplied a shellac'or similar coating over either the stain or thefiller. 1111s is essential as otherwise the solvents of the varnish orlacquer will cause the eflectknown as bleeding, which results from thestain penetrating into the varnish or lacquer composition. The oilstains have the desirable property of penetrating into the wood-surface,but they are open to several material objections. Owing to thepreliminary treatment given the Application November 5, 1929, Serial No.405,054

dyes to render them available in the oil stain compositions, theresultant product is not light fast, and it is also subject to theso-called bleeding efi ect. Furthermore any excess of fatty acidpresentjin such compositions affects the practicability and thedurability-of the surface finish, producing such effects as retardeddrying and as checking.

The spirit stains, which utilize aniline dye bases so treated as to besoluble in alcohol, are 10 not used ,very extensively because they arealso subject to a number of undesirable qualities, such as lack ofpenetration into the wood surface, and lack of permanency of color andfading qualities similar to those of the oil-type stains. The spiritstains are also subject to the bleeding effect, and in many instancesalso give rise to grain raising.

It is apparent, therefore, that all of the prior art types of stains areopen to a number of obiections, and none of the prior art staincompositions is entirely free from the objectionable qualities referredto.

Among the objects and advantages of the present invention is theproduction of wood stains which shall have the property of penetratingthe wood surface to which they are applied without producing anysubstantial grain raising, and which at the same time will not exhibitthe fading and bleeding properties of the prior art' stains.

Other objects and advantages will appear from the more detaileddescription set forth below, it being understood however that thismoredetailed description is given by way of illustration only, and not byway of limitation, since various changes may be made therein by thoseskilled in the art without departing from the scope and spirit of thisinvention. v

In the more detailed description set forth below, the invention will beparticularly illustrated 4 in connection with the use of aniline dy'es,since these are the most utilized materials employed ,in wood staining,compositions, it being under.-

stood, however, that other dyeing or staining materials may be employedwhen such other ma- 4 terials are properly considered equivalents of theg aniline dyes in this art.

In carrying out the invention of the present disclosure, a wood-staincomposition is utilized which contains preferably an aniline dye and apenetrant vehicle therefor. The aniline dyes particularly utilized inthis connection may be described as having the light fast ornon-bleeding properties of the water soluble aniline dyes. The penetrantvehicle should besuch as to carry the chosen dye or stain substantiallyinto the wood instead of to deposit it substantially only upon thesurface of the wood as is the case with water stain. The vehicle shouldcarry the stain or dye into the wood and below the mere surface portionthereof and should then rapidly evaporate leaving the pores of the woodimpregnated with the stain. As ingredients of such vehicles that are ofspecial use in connection with the present invention and that have givenremarkable re sults therein, there may be mentioned the class ofderivatives known as ether-alcohols, that is that group of organiccompounds which include both an ether and an alcohol group. The glycolethers are particularly desirable in this connection, and there may bespecifically mentioned as illustrative of such compounds mono-ethylether of ethylene glycol, diethylene-glycol mono-ethyl etherandmono-butyl ether of diethylene glycol. The solubility of the anilinedyes in such glycol ethers vary, and consequently and preferably asolvent vehicle is chosen which is a complete solvent for the particulardye or stain to be utilized in the given composition.

Diethylene-glycol mono-ethyl ether, is a particularly valuable penetrantvehicle component, since all of the desirable aniline dyes used for woodstains appear to be soluble in this material. Mono butyl ether ofdiethylene glycol may also .be considered an excellent solvent inconnection with the present invention, but is not as available asdiethylene-glycol mono-ethyl ether for the reason that mono-butyl etherof diethylene glycol does not appear to have as great a solvent actionon the black aniline dyes, particularly of the nigrosine type. Monoethylether of ethylene glycol is also a valuable solvent, but like monobutylether of diethylene glycol does not have as great a solvent action onthe aniline blacks as does diethylene-glycol mono-ethyl ether.Consequently, diethylene-glycol mono-ethyl ether may be looked upon asthe best solvent for utilization in connection with the presentinvention. A single ether-alcohol, particularly a glycol ether, may beused in preparing the stain base, or mixtures of the ether-alcohols maybe employed depending on the particular types of dyes utilized, and anydesired diluent materials maybe employed with the particularether-alcohol or glycol etthg chosen for the main solvent for the dye sa As illustrative of the several types of aniline dyes that may beutilized in connection with the solvents set forth above, andparticularly diethylene-glycol mono-ethyl ether, the following may benoted: as blacks, Buffalo black NBR cone. and number 4523 Nigro blackconc.; as reds, Azo Rubine ex cone. and amacid brilliant croecine 3BAconc.; as orange, orange A conc.; as yellow, fast wool yellow 3GL; asbrown, Resorcine brown; and

as green, alkali green 260.

The aniline dye in solution in the penetrant vehicle component of thecharacter set forth above produces an excellent stain base that,particularly when mixed with the additional solvent and vehicleingredients below referred to, penetrates into the wood, and alsoproduces a stain which is non-bleeding and is fast to light. In general,since the glycol ethers, and particularly those of the character ofdiethylene-glycol mono-ethyl ether, are rather slow drying andhygroscopic, it is desirable to utilize a composite solvent mix in orderto secure speed in drying and setting of the' composition. Consequentlyadditional solvent and vehicle ingredients may be added to the chosenstain base of dye in glycol ether, to secure the particular propertiesdesired in the final composition. In choosing such additional solventsor diluents or other vehicles, several factors should be kept in mind.The solvents or diluents or additional vehicles utilized shouldpreferably be inexpensive enough to make them commercially practicablefor the use in hand. They should be solvents of or miscible with the dyedissolved in the penetrant vehicle component, and should be of suchnature as to penetrate the wood and carry the dye into the wood.Further, the composition should desirably include a water eliminant inorder to give the composition properties of resistance to moistureretention. And further, the combination of solvents or diluents orvehicles should be such that the final composition exhibits a properevaporation curve to dispel both the diethylene-glycol mono-ethyl etheror other penetrant vehicle and any moisture present from the woodsurface.

As illustrative of ingredients that may be utilized in order to increasethe rapidity of drying and setting of the composition, the aliphaticalcohols, such as methyl alcohol, ketones, such as acetone, and theesters of the aliphatic alcohols, particularly .the fatty acid esters ofsuch materials, namely ethyl acetate, etc. may be utilized. Methylalcohol or methanol is a particularly valuable ingredient for use inthis connection.

Ingredients that give the composition resistance to moisture retentioninclude hydrocarbon distillates, particularly the coaltar distillates,benzol, toluol, solvent naphtha, the xylols, ethyl benzene, etc. Toluolis particularly valuable in this connection. Many of the esters, such asbutyl propionate and butyl acetate are also exemplary of materials whichhave water eliminant properties, but such materials as these esters areslower drying and cost more, and therefore are not as valuable ingeneral in compositions of the present character as are the hydrocarbonsubstances, such as toluol.

Parts methylene-glycol mono-ethyl ether 1 Methyl alcohol 9 Toluol 6 Thiscomposition may be utilized with, for example, from 2 to 2% ounces ofthe particular dye to one gallon of the composite solvent. The amount ofdye utilized depends on the particu- .lar dye itself and its degree ofconcentration,

and the depth of color required in the particular stain. Further, thestrength of the dye stain may be varied by the amount ofdiethylene-glycol mono-ethyl ether utilized, for example.

In making up these compositions, the aniline dye or stain, such as thenigrosines, may be allowed to stand with the diethylene-glycol monoethylether until the dye dissolves, after which the'other ingredients may beadded.

The composition set forth in the above example gives an excellent stain,and a very satisfactory drying effect and rapidity of setting areobtained. The proportions of solvents and ingredients in the compositesolvent may of course be varied within-wide limits, and further, assetforth above, except for particular purposes, the

Both the aliphatic al-- cohols and similar ingredients and thehydrocaradditional diluents or solvents may be substituted by othermaterials.

In order to increase the dye strength of the stain composition, thefollowing may beused:

in connection with 4 ounces of the aniline dye per gallon of thecomposite solvent. Other mixtures include 1 or 2 parts by volume ofdiethylene-glycol mono-ethyl ether to 9 parts of methanol and 5 partstoluol. But it should be noted again that these compositions are givenmerely by way of illustration and exemplify very desirable types ofstain compositions that may be utilized in connection with the presentinvention; but as stated above, these additional solvents and therapidly drying ingredients such as methanol and water eliminants such astoluol may be substituted by other ingredients, depending on theparticular conditions under which the compositions are to be utilized.

In applying these stain compositions to wood, and in order to comparethe simplified methods which result from the utilization of the presentcompositions, the following examples may be considered. In treating anopen grain wood, such as oak, the wood may be stained, and then thestain allowed to dry. Following this, a filler, such as a silex filler,may be rubbed in, and following the fllling treatment, a lacquer orvarnish may be applied. In treating a close grain wood, such as birch,the stain may be applied to the wood article, and then allowed to dry,following which the lacquer or varnish or other finishing coatingcomposition may be applied. Not only are the staining methodsconsiderably simplified and made moreeconomic'al by use oft'he staincompositions of the present invention, but stains are obtained which arelight-fast and consequently do not fade, and also which aresubstantially non-bleeding. In addition, the stain or dye penerates intothe wood.- All of these factors are very material in the production ofstains on wood articles.

While for the production of stain compositions, particularly fortreating wood surfaces, the

compositions hereinabove described may be utilized, other additionalingredients may be added to the composition for particular purposes. Forexample, fillers, such as silex, or oil paste fillers, may be mixed withthe new stain composition to make a combination stain and filler.

A combination stain and filler having a transparent colorthat is fast tolight, may accordingly be produced under this disclosure, whereas thisresult hasnever heretofore been possible.

In addition, the stains produced in accordance with this disclosure, orthe stain bases, may be added to or incorporated with cellulose ester orether solutions and lacquers, as well as other lacquers particularlythose containing solvents 2. As a wood stain composition, awater-soluble aniline, dye, a volatile solvent therefor including aglycol ether, a volatile hydrocarbon component selected from the groupconsisting of benzol, toluol, solvent naphtha, xylol, ethyl benzene, andcoal tar distillates; and a rapidly ,volatilizing organic componentincreasing the rapidity of drying and setting of the composition, saidrapidly volatilizing organic component being selected from the groupconsisting of the aliphatic alcohols, ketones, and the esters of thealiphatic alcohols, the components being present in proportions to yielda substantially light-fast, penetrating, non-bleeding, non-grain raisingwood stain.

3. As a wood stain composition, a water-soluble aniline dye, a volatilesolvent therefor including a glycol ether, and a volatile hydrocarboncomponent selected from the group consisting of ben-v zol, toluol,xylol, ethyl benzene, hydrocarbon distillates, solvent naphtha, and coaltar distillates.

4. As a wood stain composition, a water-soluble aniline dye, a volatilesolvent therefor including a glycol ether, and a rapidly volatilizingorganic co mponent increasing the rapidity of drying and setting of thecomposition, said rapidly volatilizing organic component being selectedfrom the group consisting of the aliphatic alcohols, ketones, and theesters of the aliphatic alcohols.

5. A composition adapted for the production of. wood stains upondispersion with a lower aliphatic alcohol and a liquid member of thebenzene series of hydrocarbons, said composition consisting of awater-soluble aniline dye and a glycol ether.

6. A composition adapted upon dispersion with a lower aliphatic alcoholand a liquid member of the benzene series of hy'drocarbons to produce acombination wood stain and filler, said composition consisting of awater-soluble aniline dye, a glycol ether, and a wood filler.

7. A wood stain composition, comprising a water-soluble aniline dye, aglycol ether, a lower aliphatic alcohol, and a member of thebenzeneseries of hydrocarbons.

8. A wood stain containing a water-soluble aniline dye in solution in apenetrant composite vehicle containing a high boiling point solventincluding a glycol ether for the dye and a compatible rapidlyvolatilizing component, the ingredients being present in proportions toyield a wood stain of light fast, non-fading, non-grain dilution withmethanol and toluol in the proportions by volume of glycol ether 1:methanol 9: toluol 6, of yielding a wood stain that is substantiallylight fast, non-fading, non-grain raising,

and not bleeding into lacquer and varnish topcoats.

10. A wood stain composition comprising a water soluble aniline dye,monoethyl ether of etheylene glycohmethanol and toluol. 11. A wood staincomposition comprising a water soluble aniline dye, monobutyl ether ofdiethylene glycol, methanol and toluol.

EDWARD a. BUSH.

